Wire and cable fault test method

Wire and cable manufacturers will encounter the phenomenon of wire disconnection or short circuit, which is a headache for the quality inspection department of the enterprise. Some enterprises have wire and cable fault detection instrument, some do not use the existing equipment to find the fault point needs a simple and applicable calculation method, here introduced this wire and cable fault calculation method, although in the previous cable newspaper saw here also put forward our idea of finding breakpoints and short circuits.
Open circuit: the capacitance method calculates L = UX * S/P,(L is the disconnection distance, S is the cable length; UX measures the end disconnection working capacitance). The difference between the measurement results of this method and the actual disconnection point is quite large, which wastes manpower and material resources.
Short break: this method of calculating resistance is L = A * S/(A B),(l is the disconnection distance, s is the cable length; A, B measuring end short-circuit resistance) this method is the most effective method for cable enterprises, but there is also the problem of resistance measurement accuracy.
After continuous analysis and summary of the accident, we found that there is a rule of wire disconnection that is obvious: local telephone lines, pairs or groups of wires, etc. That is, the open circuit capacitance we measure is larger than the normal single-wire capacitance, and the capacitance of the normal wire is very close without much change. It is also inevitable that the open circuit capacitance is large. No matter whether we measure the-end or B- end measurement, it is the ground or the normal wire pair, so there are not only one pair but also the coupling capacitance of the ground and other wire pairs.